# Bean Validation 2.0

Bean Validation 2.0 added more alignments with Java 8 and CDI, and bring a series of new annotations.

* Supports Java 8 Date time and `Optional`.
* Supports annotations applied on parameterized type, such as `List<@Email String> emails`.
* Add a series of new annotations, eg. `@Email`,`@NotEmpty`, `@NotBlank`, `@Positive`, `@PositiveOrZero`, `@Negative`, `@NegativeOrZero`, `@PastOrPresent` and `@FutureOrPresent`.

Let's create a simple example to experience it.

```
public class Todo implements Serializable {

    @NotNull
    @NotBlank
    private String name;

    private String description;

    @PastOrPresent
    private LocalDateTime creationDate = LocalDateTime.now();

    @Future
    private LocalDateTime dueDate = LocalDateTime.now().plusDays(2);

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public LocalDateTime getCreationDate() {
        return creationDate;
    }

    public void setCreationDate(LocalDateTime creationDate) {
        this.creationDate = creationDate;
    }

    public LocalDateTime getDueDate() {
        return dueDate;
    }

    public void setDueDate(LocalDateTime dueDate) {
        this.dueDate = dueDate;
    }


}
```

Create a test to verify it.

```java
@RunWith(Arquillian.class)
public class TodoTest {

    @Deployment(name = "test")
    public static Archive<?> createDeployment() {

        JavaArchive archive = ShrinkWrap.create(JavaArchive.class)
                .addPackage(Todo.class.getPackage())
                //.addAsManifestResource("META-INF/test-persistence.xml", "persistence.xml")
                //.addAsResource("persons.json", "persons.json")
                .addAsManifestResource(EmptyAsset.INSTANCE, "beans.xml");
        // System.out.println(archive.toString(true));
        return archive;
    }

    @Inject
    Logger LOG;

    @Inject
    ValidatorFactory validatorFactory;

    @Inject
    Validator validator;

    @Test()
    public void testInvalidTodo() {
        Todo todo = new Todo();
        assertNull(todo.getName());
        Set<ConstraintViolation<Todo>> violations = validatorFactory.getValidator().validate(todo);
        LOG.log(Level.INFO, "violations.size ::" + violations.size());
        assertTrue(violations.size() > 0);
    }

    @Test()
    public void testInvalidTodo2() {
        Todo todo = new Todo();
        Set<ConstraintViolation<Todo>> violations = validator.validate(todo, Default.class);
        LOG.log(Level.INFO, "violations.size ::" + violations.size());
        assertTrue(violations.size() > 0);
    }

    @Test()
    public void testInvalidDueDate() {
        Todo todo = new Todo();
        todo.setName("test");
        todo.setDueDate(LocalDateTime.now());
        Set<ConstraintViolation<Todo>> violations = validator.validate(todo, Default.class);
        LOG.log(Level.INFO, "violations.size ::" + violations.size());
        assertTrue(violations.size() == 1);
    }

}
```

`Validator` or `ValidatorFactory` is available for injection, you can inject them into your beans as other CDI beans. `validate` method will return a collection of `ConstraintViolation`.

Grab the [source codes](https://github.com/hantsy/ee8-sandbox) from my GitHub account, and have a try.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://hantsy.gitbook.io/java-ee-8-by-example/bv.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.